TECHNICAL FIELD
[0001] The present invention relates to a vehicle stop support system for supporting stop
of a vehicle which is traveling.
BACKGROUND ART
[0002] There has been known a system for causing a vehicle to stop on behalf of a driver,
in the event that the driver becomes unable to continue safe driving due to a sudden
change in his/her body condition or the like (such a driver will hereinafter be referred
to also as "driver in an emergency condition"). For example, in the following Patent
Document 1, there is disclosed a system for causing a vehicle to stop in an evacuation
space, upon detection of a physical abnormality of a driver. Further, as an improvement
to such a system, in the Patent Document 2, there is disclosed prohibiting a vehicle
from stopping in an area having poor visibility. This vehicle stop support system
makes it possible to keep a driver in an emergency condition, a fellow passenger and
other road user away from danger of a vehicle collision, and rescue the driver after
stop of the vehicle.
CITATION LIST
[Patent Document]
SUMMARY OF INVENTION
[Technical Problem]
[0004] In recent years, along with development of technologies for automated vehicle driving,
technologies concerning components such as a high-accuracy geographic map and a vehicle-mounted
camera have been making great progress. In the field of vehicle stop support systems,
it is expected to effectively utilize information provided from these components to
support vehicle stop so as to further contribute to rescue of a driver in an emergency
condition.
[0005] The present invention has been made to fulfill this demand, and an object of the
present invention to provide a vehicle stop support system capable of supporting vehicle
stop so as to further contribute to rescue of a driver in an emergency condition.
[Solution to Technical Problem]
[0006] In order to achieve the above object, the present invention provides a vehicle stop
support system for supporting stop of a vehicle which is traveling. The vehicle stop
support system comprises: an abnormality detection part for detecting a physical abnormality
of a driver; a target time period setting part for setting a target time period based
on the abnormality detected by the abnormality detection part; a candidate detection
part for detecting a plurality of stop point candidates which exist in a traveling
direction of the vehicle; a required time period estimation part for estimating a
time period required to reach each of the stop point candidates; a stop point setting
part for setting a stop point; and a vehicle control part for controlling the vehicle
to travel to the stop point and stop at the stop point, wherein the stop point setting
part is operable to set the stop point from one or more of the plurality of stop point
candidates each satisfying a condition that the required time estimated with respect
thereto is equal to or less than the target time period.
[0007] In the vehicle stop support system of the present invention having the above feature,
the target time period is set based on the physical abnormality of the driver detected
by the abnormality detection part. Thus, for example, by setting a relatively short
target time period with respect to a physical abnormality having a relatively high
urgency, it becomes possible to quickly stop the vehicle to start a rescue operation.
On the other hand, by setting a relatively long target time period with respect to
a physical abnormality having a relatively low urgency, it becomes possible to set
the stop point from among a larger number of stop point candidates.
[0008] Preferably, the vehicle stop support system of the present invention further comprises
a storage part preliminarily storing therein a plurality of values of the target time
period each corresponding to a respective one of a plurality of physical abnormalities,
wherein the target time period setting part is operable to read, from the storage
part, one of the stored values of the target time period which corresponds to the
abnormality detected by the abnormality detection part.
[0009] According to this feature, it is possible to suppress a situation where, due to disturbance
or the like, the target time period setting part undesirably operates to set the target
time period to an inappropriately-short or-long value. This makes it possible to set,
as the target time period, a sufficient time period required for the physical abnormality
of the driver.
[0010] Preferably, in the vehicle stop support system of the present invention, the vehicle
control part is operable, when the abnormality detection part detects the abnormality,
to control the vehicle to travel at a vehicle speed which is lower than a predetermined
value,
[0011] According to this feature, it is possible to suppress an inertia force acting on
the driver during stop of the vehicle. This makes it possible to allow the driver
in an emergency condition to wait for rescue without a large postural imbalance.
[Effect of Invention]
[0012] The present invention can provide a vehicle stop support system capable of supporting
vehicle stop so as to further contribute to rescue of a driver in an emergency condition.
BRIEF DESCRIPTION OF DRAWINGS
[0013]
FIG. 1 is a block diagram showing a vehicle stop support system according to one embodiment
of the present invention.
FIG. 2 is an explanatory diagram of a first pattern.
FIG. 3 is an explanatory diagram of a second pattern.
FIG. 4 is an explanatory diagram of a third pattern.
FIG. 5 is a flowchart showing a processing routine to be executed by an ECU.
FIG. 6 is a table showing a correspondence relationship between a disorder/disease
and a target time period.
FIG. 7 is a graph for explaining a visibility risk.
FIG. 8 is a graph for explaining a relative speed risk.
DESCRIPTION OF EMBODIMENTS
[0014] With reference to accompanying drawings, one embodiment of the present invention
will now be described. For the sake of facilitating understanding of the description,
the same reference sign is assigned to the same elements or components in the figures,
and duplicated description of such a component will be omitted.
[0015] First of all, with reference to FIG. 1, the configuration of a vehicle stop system
1 (hereinafter referred to as "system 1") according to this embodiment will be described.
FIG. 1 is a block diagram showing the system 1. The system 1 is equipped in a vehicle,
and operable to support stop of the vehicle which is traveling, as an emergency measure.
In this Description, a vehicle equipped with the system 1 will be referred to as "vehicle
2".
[0016] Further, in this Description, a forward movement direction of the vehicle 2 will
be referred to as "front" or "forward", and a backward movement direction of the vehicle
2 will be referred to as "back" or "backward". Further, a left side with respect to
the vehicle 2 oriented in the forward movement direction will be referred to as "left"
or "leftward".
[0017] The system 1 comprises a vehicle exterior camera 31, a vehicle interior camera 32,
a navigation device 33, an accelerator pedal sensor 34, a brake pedal sensor 35, a
steering sensor 36, and an ECU (Electronic Control Unit) 5.
[0018] The vehicle exterior camera 31 is operable to take an image of the outside of the
vehicle 2, particularly, the front of the vehicle 2, to acquire image data thereabout.
The vehicle exterior camera 31 is composed of, e.g., an image sensor, and installed
to a non-illustrated rearview mirror of the vehicle 2. The vehicle exterior camera
31 is also operable to transmit a signal corresponding to the acquired image data,
to the ECU 5.
[0019] The vehicle interior camera 32 is operable to take an image of the inside of the
vehicle 2 to acquire image data thereabout. Specifically, the vehicle interior camera
32 is operable to take an image of a range including the upper body of a driver in
a passenger compartment of the vehicle 2. The vehicle interior camera 32 is composed
of, e.g., an image sensor, and installed to a non-illustrated instrument panel of
the vehicle 2. The vehicle interior camera 32 is also operable to transmit a signal
corresponding to the acquired image data, to the ECU 5.
[0020] The navigation device 33 is capable of providing various information to a passenger
of the vehicle 2. The navigation device 33 stores therein map information, or is capable
of acquiring map information through communication with a server outside the vehicle
2. The map information contains a road configuration, an upper speed limit assigned
to each road in accordance with law or regulation, and a traffic state of each road.
The map information also contains information regarding points where ambulances are
deployed, such as a fire department and a medical center. The navigation device 33
comprises a sensor for detecting the location of the vehicle 2, such as a GPS (Global
Positioning System) senor or a self-contained navigation sensor. The navigation device
33 is operable to provide, to the passenger, map information, and information regarding
the position of the vehicle 2 on the map, a time period required for the vehicle 2
to reach a given point, and others, with sound or display. The navigation device 33
is configured to be communicable with the ECU 5, and operable, in response to a request
from the ECU 5, to transmit a signal to the ECU 5, thereby providing a variety of
information thereto.
[0021] The accelerator pedal sensor 34 is a sensor for detecting a depression amount of
a non-illustrated accelerator pedal of the vehicle 2. The accelerator pedal sensor
34 is operable to transmit, to the ECU 5, a signal corresponding to the detected depression
amount.
[0022] The brake pedal sensor 35 is a sensor for detecting a depression amount of a non-illustrated
brake pedal of the vehicle 2. The brake pedal sensor 35 is operable to transmit, to
the ECU 5, a signal corresponding to the detected depression amount.
[0023] The steering sensor 36 is a sensor for detecting a steering direction and a steering
angle of a non-illustrated steering wheel of the vehicle 2. For example, the steering
sensor 36 is provided with an encoder, and operable to count the number of slits in
a plate rotatable together with the steering wheel. The steering sensor 36 is operable
to transmit, to the ECU 5, a signal corresponding to the detected steering direction
and steering angle.
[0024] The ECU 5 is a control device for controlling components through signal transmission
and receiving with respect thereto. The ECU 5 is partly or entirely constructed as
an analog circuit or as a digital processor. ECU 5 comprises an abnormality detection
part 51, a target time period setting part 53, a candidate detection part 55, a required
time period estimation part 57, a risk estimation part 59, a stop point setting part
67, a vehicle control part 68, and a storage part 69.
[0025] In FIG. 1, each function of the ECU 5 is shown as a block. However, it should be
understood that a software modules incorporated in the analog circuit or digital processor
of the ECU 5 needs not necessarily be divided as shown in FIG. 1. That is, each of
the function block shown in FIG. 1 may be further segmentalized, or two or more of
the function blocks may be integrated into a single function block which has functions
of the two or more function blocks. It is apparent to a person of ordinary skill in
the art that the internal configuration of the ECU 5 may be appropriately modified
as long as the ECU 5 is configured to be capable of executing the after-mentioned
processing routine.
[0026] The abnormality detection part 51 is configured to detect a physical abnormality
of the driver of the vehicle 2. The abnormality detection part 51 is operable to detect
the physical abnormality of the driver, based on signals received by the ECU 5 from
the vehicle interior camera 32, the accelerator pedal sensor 34, the brake pedal sensor
35 and the steering sensor 36.
[0027] For example, the abnormality detection part 51 is operable to subject the image data
acquired by the vehicle interior camera 32 to given processing to identify the upper
body, head region, face, eyes, etc., of the driver and acquire information regarding
the identified regions. Further, the abnormality detection part 51 is operable to
detect information regarding driving manipulations of the driver, based on the signals
received from the accelerator pedal sensor 34, the brake pedal sensor 35 and the steering
sensor 36. Then, the abnormality detection part 51 is operable to perform a given
calculation based on the acquired information to detect the state of consciousness
of the driver, an open/closed state of the eyes of the driver, a line-of-sight direction
of the driver, the position of the center of gravity of the driver, etc.
[0028] Further, the abnormality detection part 51 is operable to determine whether or not
the line-of-sight direction of the driver is coincident with a traveling direction
of the vehicle 2. Specifically, the abnormality detection part 51 is operable to determine
whether or not the line-of-sight direction of the driver falls within a given range
including the traveling direction of the vehicle 2. Additionally, the abnormality
detection part 51 is operable to determine whether or not the center-of-gravity position
of the driver is adequate, based on a distance from a seating surface of a seat on
which the driver sits to the center of gravity of the driver.
[0029] Then, the abnormality detection part 51 is operable to perform a given calculation
based on the above acquired information, to estimate a disorder/disease developing
in the body of the driver. Examples of the disorder/disease include cerebrovascular
diseases, heart diseases, gastrointestinal diseases, and syncope, which are difficult
for the driver himself/herself to predict sudden development thereof.
[0030] The target time period setting part 53 is operable to set a target time period, based
on the abnormality detected by the abnormality detection part 51. As will be described
later, the target time period setting part 53 is operable to set, as the target time
period, a time period corresponding to a disorder/disease developing in the body of
the driver.
[0031] The candidate detection part 55 is configured to detect a stop point candidate. Here,
a point at which the system 1 causes the vehicle 2 to stop will be referred to as
"stop point", and a point which has a potential to become the stop point will be referred
to as "stop point candidate". The candidate detection part 55 is operable to acquire
map information based on a signal received from the navigation device 33, and detect
a plurality of stop point candidates each of which exists in the traveling direction
of the vehicle 2 in the acquired map information, and satisfies a given condition.
[0032] The required time period estimation part 57 is configured to estimate a time period
required to reach each of the stop point candidates detected by the candidate detection
part 55. Specifically, the required time period estimation part 57 is operable to
search a course to each of the stop point candidates and determine a vehicle speed
pattern of the vehicle 2 when the vehicle 2 travels along the course, and to estimate
a time period required for the vehicle 2 to reach each of the stop point candidates,
based on a corresponding set of the course and the vehicle speed pattern.
[0033] The risk estimation part 59 is configured to estimate a rear-end collision risk at
each of the stop point candidates detected by the candidate detection part 55. Here,
the "rear-end collision risk" means an index regarding a risk that, when assuming
that the vehicle 2 stops at each of the stop point candidates, the vehicle 2 will
be rear-ended by a following vehicle. The degree of the rear-end collision risk varies
depending on a point. The details of estimation of the rear-end collision risk will
be described later.
[0034] The stop point setting part 67 is configured to narrow down the plurality of stop
point candidates detected by the candidate detection part 55, based on a given condition,
or set one of the stop point candidates, as the stop point. The details of setting
of the stop point will be described later.
[0035] The vehicle control part 68 is configured to control the behavior of the vehicle
2. Specifically, the vehicle control part 68 is operable to transmit control signals,
respectively, to an engine 41 and a brake 42 of the vehicle 2, so as to control the
vehicle speed of the vehicle 2. Further, the vehicle control part 68 is operable to
subject the image data acquired by the vehicle exterior camera 31, to given processing,
to detect a demarcation line of a road on which the vehicle 2 is traveling. Then,
the vehicle control part 68 is operable to transmit, to an electric power steering
43, a control signal created based on the detected demarcation line, to control the
traveling direction of the vehicle 2.
[0036] The storage part 69 is composed of, e.g., a non-volatile memory, and stores therein
a variety of information. The information stored in the storage part 69 is read by
the abnormality detection part 51 and others, and used for various calculations.
[0037] Next, with reference to FIGS. 2 to 4, control of the vehicle 2 by the system 1 will
be described. FIGS. 2 to 4 show an environment where it is stipulated that any vehicle
shall travel in the left lane, by law or regulation, like the Japanese traffic environment.
A road 8 in FIGS. 2 to 4 is a four-lane road, wherein two lanes on one side consists
of an overtaking lane 81 and a cruising lane 82. The system 1 is operable, upon satisfaction
of a given condition during traveling of the vehicle 2, to control the vehicle 2 to
stop at a stop point SP on behalf of the driver, as an emergency measure. The stop
point SP is set in one of the following three patterns.
[First Pattern]
[0038] FIG. 2 shows a first pattern in which the stop point setting part 67 (see FIG. 1)
of the system 1 operates to set a point within the road 8, as the stop point SP. Specifically,
FIG. 2 shows a situation where a given condition is satisfied when the vehicle 2 is
traveling in the overtaking lane 81, and a point located on the overtaking lane 81
in the traveling direction of the vehicle 2 is set as the stop point SP. In this situation,
the vehicle control part 68 (see FIG. 1) of the system 1 operates to transmit a control
signal to the electric power steering 43 (see FIG. 1) so as to controllably cause
the vehicle 2 to keep traveling in the overtaking lane 81.
[Second Pattern]
[0039] FIG. 3 shows a second pattern in which the stop point setting part 67 of the system
1 operates to set a road shoulder 83 of the road 8, as the stop point SP. Specifically,
FIG. 3 shows a situation where a given condition is satisfied when the vehicle 2 is
traveling in the cruising lane 82, and a road shoulder 83 existing in the traveling
direction of the vehicle 2 is set as the stop point SP. In this situation, the vehicle
control part 68 of the system 1 operates to transmit a control signal to the electric
power steering 43 so as to controllably cause the vehicle 2 to keep traveling in the
cruising lane 82 and move forwardly and obliquely leftwardly in the vicinity of the
stop point SP.
[Third Pattern]
[0040] FIG. 4 shows a third pattern in which the stop point setting part 67 of the system
1 operates to set an emergency parking bay 84 provided on the lateral side of the
road 8, as the stop point SP. Specifically, FIG. 4 shows a situation where a given
condition is satisfied when the vehicle 2 is traveling in the overtaking lane 81,
and an emergency parking bay 84 existing in the traveling direction of the vehicle
2 is set as the stop point SP. In this situation, the vehicle control part 68 of the
system 1 operates to transmit a control signal to the electric power steering 43 so
as to controllably cause the vehicle 2 to first move from the overtaking lane 81 to
the cruising lane 82 and to keep traveling in the cruising lane 82 and move forwardly
and obliquely leftwardly in the vicinity of the stop point SP.
[0041] In any of the first to third patterns, the vehicle control part 68 operates to, until
the vehicle 2 reaches the vicinity of the stop point SP, transmit a control signal
to the engine 41 and the brake 42 so as to control the vehicle speed of the vehicle
2 such that it becomes lower than 50 lm/h. Then, the vehicle control part 68 operates
to controllably cause the vehicle 2 to stop at the stop point SP. After stop of the
vehicle 2, the system 1 operates to blink a blinker and/or sound an alarm to prevent
the vehicle 2 from being rear-ended by a following vehicle, and inform the outside
of a fact that the driver of the vehicle 2 is in need of rescue.
[0042] Next, with reference to FIGS. 5 to 8, a processing routine to be executed by the
ECU 5 (see FIG. 1) will be described. FIG. 5 is a flowchart showing the processing
routine to be executed by the ECU 5. During traveling of the vehicle 2, this professing
routine will be repeatedly executed with a given period. FIG. 6 is a table showing
a correspondence relationship between a disorder/disease and the target time period.
FIG. 7 is a graph for explaining a visibility risk. FIG. 8 is a graph for explaining
a relative speed risk. It should be noted that processing to be executed by each of
the function blocks of the ECU 5 is also described as being executed by the ECU 5,
in the lump, for the sake of simplicity of description.
[0043] First of all, in step S1 shown in FIG. 5, the ECU 5 operates to detect the body condition
of the driver of the vehicle 2. Specifically, the ECU 5 operates to detect, based
on the image data acquired by the vehicle interior camera 32 (see FIG. 1), the state
of consciousness of the driver, the open/closed state of the eyes of the driver, the
line-of-sight direction of the driver, the center-of-gravity position of the driver,
etc.
[0044] In step S2, the ECU 5 operates to determine whether or not the driver has a physical
abnormality. Specifically, the ECU 5 operates to determine, based on a result of the
detection in the step S1, whether or not the driver has a physical abnormality which
causes the driver to become unable to drive the vehicle 2 safely. For example, the
ECU 5 may be configured to quantify the degree of consciousness of the driver, and,
when the resulting quantified value is less than a given threshold, determine that
the driver has a physical abnormality. When the driver is determined not to have any
physical abnormality (S2: NO), the ECU 5 operates to terminate the vehicle stop support
processing routine. On the other hand, when the driver is determined to have a physical
abnormality (S2: YES), the ECU 5 proceeds to step S3.
[0045] In the step S3, the ECU 5 operates to estimate a disorder/disease of the driver.
Specifically, the ECU 5 operates to estimate, based on the result of the detection
in the step S1, a disorder/disease developing in the body of the driver. The ECU 5
is capable of estimating that one of subarachnoid hemorrhage, myocardial infarction,
hypoglycemia and epilepsy develops.
[0046] In step S4, the ECU 5 is operable to set a target time period. Specifically, the
ECU 5 is operable to set, as the target time period, a time period corresponding to
the disorder/disease estimated in the step S3, based on the table shown in FIG. 6.
[0047] Data of the table shown in FIG. 6 is preliminarily stored in the storage part 69
(see FIG. 1). In FIG. 6, values of the target time periods T1, T2, T3 are different
from each other, wherein each of the values corresponds to the degree of urgency of
a corresponding disorder/disease. For example, with respect to a disorder/disease
having a relatively high urgency and thus requiring possibly prompt rescue, a relatively
short time period is set as the target time period. On the other hand, with respect
to a disorder/disease having a relatively low urgency, a relatively long time period
is set as the target time period.
[0048] In step S5, the ECU 5 operates to detect a stop point candidate. Specifically, the
ECU 5 operates to acquire map information, based on a signal received from the navigation
device 33, and detect a plurality of points each of which exists within 5 km from
the vehicle 2 in the traveling direction of the vehicle 2, and satisfies a given condition,
as a plurality of stop point candidates. The given condition may be set based on various
factors such as properties of the vehicle 2, properties of the road on which the vehicle
2 is traveling, the body condition of the driver detected in the step S1.
[0049] In step S6, the ECU5 operates to estimate a time period required to reach each of
the stop point candidates. Specifically, the ECU 5 operates to first search, based
on a given algorithm, a course to each of the stop point candidates detected in the
step S5, and determine a vehicle speed pattern of the vehicle 2 when the vehicle 2
travels along the course. Further, the ECU 5 operates to estimate a time period required
to reach each of the stop point candidates, based on a corresponding set of the determined
course and vehicle speed pattern.
[0050] In step S7, the ECU 5 operates to narrow down the stop point candidates. Specifically,
in a case where N stop point candidates (where N is an integer of two or more) are
detected in the step S5, the ECU 5 operates, in the step S7, to select and leave less-than-N
stop point candidates each satisfying the given condition, among the N stop point
candidates, and exclude the remaining one or more stop point candidates. More specifically,
the ECU 5 operates to select and leave, among the plurality of stop point candidates
detected in the step S5, one or more stop point candidates each satisfying a condition
that the required time period estimated with respect thereto in the step S6 is equal
to or less than the target time period set in the step S4.
[0051] In step S8, the ECU 5 operates to estimate a rear-end collision risk at each of the
stop point candidates. Specifically, the ECU 5 operates to estimate a risk that, when
assuming that the vehicle 2 stops at each of the stop point candidates narrowed down
in the step S7, the vehicle 2 will be rear-ended by a following vehicle.
[0052] Here, the estimation of the rear-end collision risk will be described in detail.
The rear-end collision risk is calculated based on a "visibility risk" and a "relative
speed risk", as expressed by the following formula f1.

[0053] The "visibility risk" means a risk factor which increases along with an increase
in difficulty in visually recognizing the vehicle 2 which stops, from a following
vehicle. For example, the "visibility risk" is expressed by the graph in FIG. 7.
[0054] A "following vehicle visible distance" described in FIG. 7 means the maximum value
of a distance from a following vehicle to the vehicle 2 in a state in which the vehicle
2 which stops is visible from the following vehicle. The "following vehicle visible
distance" varies depending on a point where the vehicle 2 stops. For example, in a
situation where the vehicle 2 stops on a curved or undulating road, or in a situation
where there are obstacles such as walls or roadside trees around a road, the "following
vehicle visible distance" with respect to a point where the vehicle stops is relatively
small. On the other hand, in a situation where the vehicle 2 stops on a straight or
flat road, or in a situation where there are few obstacles around a road, the "following
vehicle visible distance" with respect to a point where the vehicle 2 stops is relatively
large.
[0055] Along with a decrease in the "following vehicle visible distance", it becomes more
difficult for a following vehicle to be braked so as to avoid a rear-end collision,
so that the "visibility risk" becomes higher. The navigation device 33 stores therein
map information, as mentioned above, and the visibility risk at each point of roads
contained in the map information is preliminarily estimated and stored in the storage
part 69 (see FIG. 1).
[0056] The "relative speed risk" means a risk factor which increases as a following vehicle
is approaching the vehicle 2 at a higher vehicle speed. For example, the "relative
speed risk" is expressed by the graph in FIG. 8. Along with an increase in relative
speed of the following vehicle with respect to the vehicle 2 which stops, the "relative
speed risk" becomes higher. The relationship between the relative speed and the "relative
speed risk" is set based on a phenomenon that, as the relative speed becomes larger,
it becomes more difficult for the following vehicle to be braked so as to avoid a
rear-end collision, and therefore a risk that the following vehicle rear-ends the
vehicle 2 becomes higher.
[0057] The ECU 5 operates to calculate the relative speed of the following vehicle with
respect to the vehicle 2 which stops (vehicle speed: 0 km/h), on the assumption that
the following vehicle is traveling at an upper speed limit assigned to each of the
stop point candidates in accordance with law or regulation. That is, in a case where
the upper speed limit assigned to the stop point candidate in accordance with law
or regulation is 100 km/h, the relative speed is also 100 km/h. Data of the graphs
shown in FIG.7 and FIG. 8 is preliminarily stored in the storage part 69 (see FIG.
1).
[0058] The ECU 5 operates to read, from the storage part 69, the "visibility risk" at each
of the stop point candidates narrowed down in the step S7, and the "relative speed
risk" corresponding to the relative speed at each of the stop point candidates. Then,
the ECU 5 operates to calculate the rear-end collision risk by assigning the read
"visibility risk" and "relative speed risk" to the formula f1. As can be understood
from the relationships shown in FIGS. 7 and 8, the rear-end collision risk becomes
higher as the following vehicle visible distance with respect to each of the stop
point candidates becomes smaller. Further, the rear-end collision risk becomes higher
as the relative speed of the following vehicle with respect to the vehicle 2 at each
of the stop point candidates becomes larger.
[0059] The ECU 5 may be configured to estimate the rear-end collision risk based on a detailed
location of each of the stop point candidates, in addition to or in place of the estimation
of the rear-end collision risk based on the formula f1. The estimation of the rear-end
collision risk based on the detailed location of each of the stop point candidates
will be described below.
[0060] A risk that the vehicle 2 is rear-ended by a following vehicle largely varies, depending
on at which of the three stop points SP as shown in FIGS. 2 to 4 the vehicle 2 stops.
A probability that the vehicle 2 is rear-ended by a following vehicle when the vehicle
2 stops at the stop point SP set in the road shoulder 83 as in the second pattern
(see FIG. 3) is empirically clearly lower than a probability that the vehicle 2 is
rear-ended by a following vehicle when the vehicle 2 stops at the stop point SP set
simply within the road 8 as in the first pattern (see FIG. 2). Further, generally,
a vehicle speed of a vehicle traveling in the overtaking lane 81 is greater than that
a vehicle traveling in the cruising lane 82. Therefore, even within the road 8, a
probability that the vehicle 2 is rear-ended by a following vehicle when the vehicle
2 stops in the overtaking lane 81 is also empirically clearly higher than a probability
that the vehicle 2 is rear-ended by a following vehicle when the vehicle 2 stops in
the cruising lane 82. Furthermore, a probability that the vehicle 2 is rear-ended
by a following vehicle when the vehicle 2 stops at the stop point SP set in the emergency
parking bay 84 as in the third pattern (see FIG. 4) is empirically clearly lower than
a probability that the vehicle 2 is rear-ended by a following vehicle when the vehicle
2 stops in the road shoulder 83.
[0061] Therefore, in the estimation of the rear-end collision risk based on the detailed
location of each of the stop point candidates, values of the rear-end collision risk
each corresponding to a respective one of the road, the road shoulder and the emergency
parking bay are preliminarily stored in the storage part 69. The value of the rear-end
collision risk at the road shoulder is smaller than the value of the rear-end collision
risk at the road. Further, the value of the rear-end collision risk at the emergency
parking bay is smaller than the value of the rear-end collision risk at the road shoulder.
In the step S8, the ECU 5 operates to read, from the storage part 69, one or more
of the values of the rear-end collision risk at the road, the road shoulder and the
emergency parking bay, corresponding to the one or more stop point candidates narrowed
down in the step S7.
[0062] In step S9, the ECU 5 operates to set a stop point. Specifically, the ECU 5 operates
to set, among the stop point candidates narrowed down in the step S7, one stop point
candidate which is smallest in terms of the rear-end collision risk estimated in the
step S8, as a stop point.
[0063] In step S10, the ECU 5 operates to control traveling of the vehicle 2 to the stop
point and stop of the vehicle 2 at the stop point. Specifically, the ECU 5 operates
to transmit control signals, respectively, to the engine 41, the brake 42 and the
electric power steering 43 (see FIG. 1) so as to controllably cause the vehicle 2
to travel to the stop point and stop at the stop point. During this process, the manipulation
of the accelerator pedal by the driver is invalidated. On the other hand, the manipulation
of the brake pedal by the driver is validated. This is because, even when the driver
is becoming unconscious, he/she is likely to attempt to stop the vehicle 2 so as to
avoid collision with an obstacle. Here, the vehicle 2 may be configured such that
a system for stabilizing the behavior of the vehicle 2, such as an anti-lock braking
system or an antiskid brake system, is activated during traveling of the vehicle 2.
[Functions/Effects of Embodiment]
[0064] In the system 1 according to the above embodiment, the target time period is set
based on the physical abnormality of the driver detected by the abnormality detection
part 51. Thus, by setting a relatively short target time period with respect to a
physical abnormality having a relatively high urgency, it becomes possible to quickly
stop the vehicle 2 to start a rescue operation. On the other hand, by setting a relatively
long target time period with respect to a physical abnormality having a relatively
low urgency, it becomes possible to set the stop point from among a larger number
of stop point candidates.
[0065] The system 1 according to the above embodiment is equipped with the storage part
69 which preliminarily stores therein a plurality of values of the target time period
each corresponding to a respective one of a plurality of physical abnormalities, wherein
the target time period setting part 53 is operable to read, from the storage part
68, one of the stored values of the target time period which corresponds to the abnormality
detected by the abnormality detection part 51.
[0066] According to this feature, it is possible to suppress a situation where, due to disturbance
or the like, the target time period setting part 53 undesirably operates to set the
target time period to an inappropriately-short or-long value. This makes it possible
to set, as the target time period, a sufficient time period required for the physical
abnormality of the driver.
[0067] In the above embodiment, the vehicle control part 68 is operable, when the abnormality
detection part 51 detects the abnormality, to control the vehicle 2 to travel at a
vehicle speed which is lower than 50 km/h,
[0068] According to this feature, it is possible to suppress an inertia force acting on
the driver during stop of the vehicle 2. This makes it possible to allow the driver
in an emergency condition to wait for rescue without a large postural imbalance.
[0069] As above, the present invention has been described based on one specific embodiment.
However, it should be understood that the present invention is not limited to the
specific embodiment. That is, various changes and modifications will be apparent to
a person of ordinary skill in the art. Therefore, unless otherwise such changes and
modifications depart from the scope of the present invention hereinafter defined,
they should be construed as being included therein.
[0070] In the above embodiment, the abnormality detection part 51 of the ECU 5 is configured
to detect the physical abnormality of the driver based on image data acquired by the
vehicle interior camera 32. However, the present invention is not limited to this
configuration. For example, in a case where the vehicle stop support system according
to the present invention is equipped in a vehicle provided with an infrared sensor
for detecting a body temperature or a pulse wave of a driver, a seat sensor for detecting
a center-of-gravity position or a pulse wave depending on the posture of the driver,
or the like, the abnormality detection part in the present invention may be configured
to detect the physical abnormality of the driver based on detection information from
such a sensor.
[0071] In the above embodiment, the required time period estimation part 57 of the ECU 5
is configured to search a course to each of the stop point candidates and determine
a vehicle speed pattern of the vehicle 2 when the vehicle 2 travels along the course.
However, the present invention is not limited to this configuration. For example,
the required time period estimation part in the present invention may be configured
to instruct the navigation device to perform search of the course and determination
of the speed pattern, and, based on information provided from the navigation device,
estimate the required time period.
LIST OF REFERENCE SIGNS
[0072]
- 1:
- vehicle stop support system (system)
- 2:
- vehicle
- 51:
- abnormality detection part
- 53:
- target time period setting part
- 55:
- candidate detection part
- 57:
- required time period estimation part
- 67:
- stop point setting part
- 68:
- vehicle control part
- 69:
- storage part
- SP:
- stop point